The present invention relates to methods and systems for patient temperature management.
It has been discovered that the medical outcome for a patient suffering from severe brain trauma or from ischemia caused by stroke or heart attack is improved if the patient is cooled below normal body temperature (38xc2x0 C.). Furthermore, it is also accepted that for such patients, it is important to prevent hyperthermia (fever) even if it is decided not to induce hypothermia.
As recognized by the present invention, the above-mentioned advantages in regulating temperature can be realized by cooling the patient""s entire body. Moreover, the present invention understands that since many patients already are intubated with central venous catheters for other clinically approved purposes anyway such as drug delivery and blood monitoring, providing a central venous catheter that can also cool the blood requires no additional surgical procedures for those patients. A cooling central venous catheter is disclosed in the above-referenced parent application.
Another cooling catheter is disclosed in U.S. Pat. No. 6,096,068. Unfortunately, the ""068 invention does not recognize the above-noted desirability of combining conventional central venous line functions with a temperature regulation function. The present invention, however, makes this critical observation and provides the solutions set forth herein.
A central venous access catheter includes first and second elongated segments, with each segment having a turbulence-inducing irregular exterior surface. A flexible articulating joint connects the first and second elongated segments. Also, a tubular conduit is disposed substantially coaxially within the first and second elongated, articulated segments. The conduit has a fluid supply lumen for transporting a pressurized working fluid to a distal end of the elongated, articulated segments. The catheter also defines at least two infusion lumens separated from the working fluid and terminating in respective ports longitudinally separated from each other. Accordingly, each infusion lumen provides a means for accessing the central venous blood supply of a patient when the catheter is placed in the central venous system of a patient. An anchor can be located proximal to at least one elongated segment and configured for affixing the catheter to the skin of a patient.
In another aspect, a central venous catheter includes at least first and second hollow metal heat exchange elements. Each element has an outer surface that is configured for inducing turbulence in a fluid flowing past the surface. A closed circuit fluid pathway conveys coolant to and from the heat exchange elements.
In one implementation, at least first and second infusion lumens separated from the coolant terminate in respective ports that are longitudinally separated from each other. Each infusion lumen provides a means for accessing the central venous blood supply of a patient when the catheter is placed in the central venous system of a patient. In another implementation, an anchor is located proximal to at least one heat exchange element and is configured for affixing the catheter to the skin of a patient.
In still another aspect, a method for treating a patient includes advancing a catheter into the central venous system of the patient, and circulating a heat exchange fluid through the catheter to exchange heat with the patient. Simultaneously with the circulating act, at least one central venous (CV) line function is undertaken.
The details of the present invention, both as to its structure and operation, can best be understood in reference to the accompanying drawings, in which like reference numerals refer to like parts, and in which: